Steam iron



FIG. 1 illustrates a top, front and side perspective view of my new design for a steam iron;

FIG. 2 illustrates a side elevational view thereof;

FIG. 3 illustrates a front elevational view thereof;

FIG. 4 illustrates a rear elevational view thereof;

FIG. 5 illustrates a top plan view thereof; and,

FIG. 6 illustrates a bottom plan view thereof. 

The ornamental design for a steam iron, as shown and described. 